Online measurement of temperature and relative humidity as marker tools for quality changes in onion bulbs during storage.

A long shelf life of onions (Allium cepa L.) is of high importance in the onion industry. Onions are dried and stored in large wooden boxes that are difficult to access. Monitoring temperature and relative humidity during these processes is challenging. Moreover, quality may change in storage without being noticed. Therefore, there is a need to find alternative methods for monitoring and controlling the drying and storage processes of onions and to identify early changes in quality during storage. The potential use of online measurements of temperature and relative humidity (RH) in the vicinity of onions was evaluated during drying and long-term storage of six onion batches (four cultivars and three selections of one of the cultivars) in commercial storage. The batches varied in bulb weight, dry matter content, firmness and disease incidence. The dry matter content and firmness decreased during storage, while the respiration rate and incidences of individual and total disease increased. Two of the batches had low storability with high disease incidences and high average temperatures and variations in the RH. The results showed that tracking the temperature and RH in the vicinity of the onions is a promising tool for improving the drying and storage processes in commercial storage and for identifying onion batches with reduced storability early in storage.

Impact of Cultivation Method and Cultivar Selection on Soluble Carbohydrates and Pungent Principles in Onions ( Allium cepa L.).

The composition of soluble carbohydrates such as fructooligosaccharides (FOS) in onions ( Allium cepa L.) plays a role regarding their digestibility, long-term storability, and processability. Qualitative and quantitative profiles of soluble carbohydrates were determined in 23 different onion samples comprising 20 cultivars grown at two different locations in 2014 and 2015. FOS concentrations were 1.1-fold higher in set grown onions than in seed grown onions ( p = 0.001). FOS levels of dehydrator cultivars were higher (overall average: 130.8 ± 42.4 g/L FOS) than those of common set and seed (61.8 ± 20.0 and 29.4 ± 14.7 g/L FOS) grown cultivars. Consequently, cultivation method (seed vs. set planting) and cultivar selection were crucial when aiming at onions with defined FOS contents. Besides FOS and other carbohydrate-related parameters, levels of alk(en)yl cysteine sulfoxides, indicating onion oil yield and pungency of onions, were determined to be different in dehydrator onions (13.1 ± 2.6 µmol/mL), seed (8.4 ± 1.3 µmol/mL), and set grown onions (7.5 ± 1.6 µmol/mL).

Characterization of the lamin analogue NMCP2 in the monocot Allium cepa.

Nuclear lamina organization is similar in metazoan and plants though the latter lack orthologs of lamins, the main components of the metazoan lamina. Current evidence suggests that Nuclear Matrix Constituent Proteins (NMCPs) are the lamin analogues in plants as these proteins share several key features: higher-order secondary structure and domain layout, subnuclear distribution, and involvement in the regulation of nuclear shape and size, as well as in higher-order chromatin organization. Previously, we studied the NMCP family in flowering plants (angiosperms), in which it comprises two phylogenetic groups: NMCP1 and NMCP2. At present, in silico information about NMCP proteins in embryophytes is relatively advanced, though very few proteins, most of them of the NMCP1 type, have been extensively studied in vivo. We previously characterized the NCMP1 protein in the monocot Allium cepa. Here, we report the key features of a second protein of this species NMCP2, which presents a conserved sequence and domain layout. Immunofluorescence and immunoelectronmicroscopy evidence co-localization of endogenous AcNMCP2 and AcNMCP1 in the lamina, while Western blotting and immunoconfocal microscopy reveal a similar pattern of expression and distribution of both NMCP proteins in different root tissues. Our results provide novel insight about endogenous NMCP2-type proteins and complete the characterization of the NMCP family in A. cepa, thus advancing the current understanding of these structural proteins constituting the plant lamina.

Efeito de extratos orgânicos de variedades de cebola sobre o quorum sensing bacteriano / Effect of organic extracts of onion varieties on bacterial quorum sensing

Muitos genes bacterianos são regulados pelo mecanismo de comunicação denominado quorum sensing (QS). Neste sistema, moléculas sinalizadoras ativam um comportamento de grupo, conforme a densidade celular, permitindo o controle da expressão gênica. Estudos sugerem o potencial de compostos extraídos de plantas sobre o QS, a exemplo da quercetina, um flavonol presente em concentrações elevadas em algumas frutas e hortaliças. Este composto é o flavonoide majoritário presente em cebola (Allium cepa), mas não existem estudos que mostrem a atividade anti-QS de extratos orgânicos deste vegetal. Este trabalho avaliou o potencial antimicrobiano e anti-QS de extratos orgânicos de cebola branca e cebola roxa, assim como de alguns de seus componentes majoritários identificados, em fenótipos regulados pelo QS como a produção de violaceína em Chrormobacterium violaceum ATCC 12472, a motilidade tipo swarming e a formação de biofilmes em Pseudomonas aeruginosa PAO1 e Serratia marcescens MG1. Extratos de cebola branca e roxa foram obtidos por extração em fase sólida utilizando coluna de poliamida e seus compostos identificados e quantificados pelas técnicas de Cromatografia líquida- ionização por elétron spray-espectrometria de massas e cromatografia líquida de alta eficiência acoplada a detector de arranjo de diodo. A atividade antimicrobiana foi avaliada pelas curvas de multiplicação de cada micro-organismo. O efeito dos compostos quercetina aglicona (inibidor do QS já relatado na literatura e encontrado no extrato de cebola roxa) e quercetina-3-ß-D-glicosideo (um dos compostos majoritários encontrados em ambos extratos) sobre os micro-organismos utilizados neste estudo foi também avaliado. Foram obtidos três extratos: cebola branca em metanol (CB-MeOH), cebola branca em metanol amônia (CBMeOH/ NH4) e cebola roxa em metanol (CR-MeOH). Os compostos quercetina 3,4'- diglicosídeio, quercetina-4-glicosídeo, quercetina-3-ß-D-glicosideo e quercetina aglicona foram os predominantes nos extratos das duas variedades de cebola. Cianidina-3-O-glicosideo também foi identificada no extrato de cebola roxa. A concentração inibitória mínima (MIC) dos extratos foi igual ou superior a 125 µg/ml (p/v) de extrato seco. Não foi observada inibição significativa da produção de violaceína em C. violaceum pelos extratos orgânicos de cebola e nem pela quercetina-3-ß-D-glicosideo, nas concentrações sub-inibitórias avaliadas. No entanto, a quercetina aglicona inibiu significativamente a produção de violaceína em todas as concentrações. A glicosilação da quercetina pode ter afetado sua atividade sobre a inibição da produção de violaceina, já que estudos mostram menor atividade biológica deste composto quando glicosilado. Para a motilidade tipo swarming em P. aeruginosa PAO1 houve inibição significativa pelo extrato de cebola roxa, em todas as concentrações estudadas. Os demais extratos não apresentaram inibição contra este micro-organismo. Para S. marcescens MG1, foi observada inibição da motilidade swarming somente na concentração de 125 µg/ml de CBMeOH/ NH4. As análises de comparação entre os dois tipos de quercetina revelaram que, embora para as duas bactérias testadas os dois compostos apresentaram atividade inibitória sobre a motilidade tipo swarming, a quercetina-3-ß-D-glicosideo foi menos eficiente que a quercetina aglicona na concentração de 125 µg/ml. A formação de biofilmes não foi influenciada pelos extratos e, inesperadamente, não se detectou inibição da formação de biofilmes por ambos tipos de quercetina avaliados. De forma geral, os extratos orgânicos de cebola mostraram pouco efeito sobre os fenótipos controlados pelo quorum sensing e a glicosilação da quercetina provavelmente explica a baixa atividade antimicrobiana e anti-QS dos extratos

Many bacterial genes are regulated by a communication mechanism called quorum sensing (QS). In this system, signaling molecules activate a group behavior according to cell density, allowing the control of gene expression. Studies suggest the inhibitory potential of compounds extracted from plants on the QS system, like quercetin, a flavonol present in high concentrations in some fruits and vegetables. This compound is the main flavonoid found in onion (Allium cepa); however, there are no studies showing the anti-QS activity of organic extracts of this plant. The objective of this work was to evaluate the antimicrobial and anti-QS potential of organic extracts of white and red onions, and their major components studied in QS-regulated phenotypes such as violacein production in Chromobacterium violaceum, swarming motility and biofilm formation in Pseudomonas aeruginosa PAO1 and Serratia marcescens MG1.White and red onion extracts were obtained by solid phase extraction using a polyamide column and its compounds were identified and quantified by Liquid Chromatography - Electron Spray-Mass Spectrometry and high performance liquid chromatography coupled to diode array detector. O The antimicrobial activity was evaluated by growth curves of each microorganism. The effect of non-glycosylated quercetin (a QS inhibitor already reported in the literature and found in red onion extract) and quercetin-3-ß-D-glycoside (one of the major compounds found in both extracts) on the microorganisms used in this study was also evaluated. Three extracts were obtained: white onion in methanol (CB-MeOH), white onion in methanol ammonia (CB-MeOH / NH4) and red onion in methanol (CR-MeOH). Our results showed that quercetin 3,4'- diglycoside, quercetin-4-glycoside, quercetin-3-ß-D-glycoside and non-glycosylated quercetin were predominant in the extracts of the two onion varieties. Cyanidin-3-O-glycoside has also been identified in the purple onion extract. The minimum inhibitory concentration (MIC) of extracts was equal or greater than 125 µg / ml (w / v) of dry extract. There was no significant inhibition of violacein production in C. violaceum by organic onion extracts or by quercetin-3-ß- D-glycoside at the sub-inhibitory concentrations evaluated. However, non-glycosylated quercetin showed a significant inhibition of violacein production in all tested concentrations. The glycosylation of Quercetin could have altered its inhibition activity towards violacein production, and in fact, some studies have shown less biological activity of some phenolic compounds when they have been glycosylated. For swarming motility in P. aeruginosa PAO1 there was significant inhibition by red onion extract, in all studied concentrations. The other extracts did not present inhibition against this microorganism. For S. marcescens MG1, inhibition of swarming motility was observed only at the concentration of 125 µg / ml of CB-MeOH / NH4. Comparative analyses between the two types of quercetin showed that, although for the two bacteria tested the two compounds showed inhibitory activity on swarming motility, quercetin-3-ß-D-glycoside was less efficient than non-glycosylated quercetin in the concentration of 125 µg / ml. Biofilm formation was not influenced by the extracts and unexpectedly, both types of quercetin evaluated did not show inhibition towards biofilm formation. In general, organic onion extracts showed little effect on quorum sensing controlled phenotypes and glycosylation of quercetin probably explains the low antimicrobial and anti-QS activity of the extracts

Higher Antioxidant Activity, Total Flavonols, and Specific Quercetin Glucosides in Two Different Onion (Allium cepa L.) Varieties Grown under Organic Production: Results from a 6-Year Field Study.

We carried out a 6-year study to assess the effect of conventional, organic, and mixed cultivation practices on bioactive compounds (flavonoids, anthocyanins) and antioxidant capacity in onion. Total flavonoids, total anthocyanins, individual flavonols, individual anthocyanins, and antioxidant activity were measured in two varieties ('Hyskin' and 'Red Baron') grown in a long-term split-plot factorial systems comparison trial. This is the first report of repeated measurements of bioactive content over an extensive time period in a single crop type within the same trial. Antioxidant activity (DPPH and FRAP), total flavonol content, and levels of Q 3,4' D and Q 3 G were higher in both varieties under fully organic compared to fully conventional management. Total flavonoids were higher in 'Red Baron' and when onions were grown under organic soil treatment. Differences were primarily due to different soil management practices used in organic agriculture rather than pesticide/ herbicide application.

Antiproliferative activity of Ontario grown onions against colorectal adenocarcinoma cells.

Cancer is the leading cause of mortality in Canada and other industrialized nations; the development of new/improved cancer therapies is desperately needed and continues to be a major focus of cancer research. Flavonoids, which are found in high levels in onions, have been shown to exert antiproliferative and potentially anti-cancer activities. To test their therapeutic potential, we assessed the antiproliferative, cytotoxic, apoptosis-inducing, and anti-migratory activities of five onion varieties grown in Ontario against human adenocarcinoma (Caco-2) cells. The properties of onion extracts were compared to pure extracts of flavonoids known to exhibit antiproliferative effects (quercetin, myricetin, and kaempferol). We compared more than one variety of onion, as agronomic and genetic factors influence the composition, as well as the quality of phytochemicals (e.g. flavonoids) in plant cultivars. We found that all onion varieties exhibited antiproliferative activity similar to purified flavonoids. The cytotoxic effects of the Stanley and Fortress onion varieties were strongest among the selected cultivars, as determined via lactate dehydrogenase (LDH) assays, while Safrane extracts showed the weakest activity. The Stanley and Lasalle cultivar extracts also had strong anti-migratory effects. Altogether these onion extracts may contain one or more compounds that may be effective anti-cancer therapies, while the Stanley extract showed the most comprehensive biological activities against Caco-2 cells.

Tracing the Geographical Origin of Onions by Strontium Isotope Ratio and Strontium Content.

The strontium (Sr) isotope ratio ((87)Sr/(86)Sr) and Sr content were used to trace the geographical origin of onions from Japan and other countries, including China, the United States of America, New Zealand, Australia, and Thailand. The mean (87)Sr/(86)Sr ratio and Sr content (dry weight basis) for onions from Japan were 0.70751 and 4.6 mg kg(-1), respectively, and the values for onions from the other countries were 0.71199 and 12.4 mg kg(-1), respectively. Linear discriminant analysis was performed to classify onions produced in Japan from those produced in the other countries based on the Sr data. The discriminant equation derived from linear discriminant analysis was evaluated by 10-fold cross validation. As a result, the origins of 92% of onions were correctly classified between Japan and the other countries.

Flavonol Glucoside and Antioxidant Enzyme Biosynthesis Affected by Mycorrhizal Fungi in Various Cultivars of Onion (Allium cepa L.).

The objective of this study was to investigate the impact of mycorrhizal symbiosis on qualitative characteristics of onion (Allium cepa L.). For this reason, five onion cultivars with different scale color and three different strains of arbuscular mycorrhizal fungi (Diversispora versiformis, Rhizophagus intraradices, Funneliformis mosseae) were used. Red cultivars, mainly 'Red Azar-shahr', showed the highest content in vitamin C, flavonols, and antioxidant enzymes. Mycorrhizal inoculation increased total phenolic, pyruvic acid, and vitamin C of onion plants. Considerable increase was observed in quercetin-4'-O-monoglucoside and isorhamnetin-4'-O-monoglucoside content in plants inoculated with Diversispora versiformis, but quercetin-3,4'-O-diglucoside was not significantly influenced. Analyses for phenylalanine ammonia-lyase (PAL) and antioxiodant enzyme activities such as polyphenol oxidase (PPO), catalase (CAT), and peroxidase (POD) revealed that all except PPO were enhanced by mycorrhizal inoculation. Overall, these findings suggested that mycorrhizal inoculation influenced biosynthesis of flavonol glucosides and antioxidant enzymes by increasing nutrient uptake or by induction of the plant defense system.

Ação genotóxica e antiproliferativa de Polygonum punctatum Elliott (Polygonaceae) sobre o ciclo celular de Allium cepa L / Genotoxic and antiproliferative action of Polygonum punctatum Elliott (Polygonaceae) on the cell cycle of Allium cepa L

RESUMO: A espécie Polygonum punctatum Elliott (Polygonaceae) é amplamente utilizada pela população como planta medicinal. O objetivo deste trabalho é o de avaliar o potencial genotóxico e mutagênico de P. punctatum utilizando raízes de bulbos e radículas em sementes germinadas de Allium cepa através do teste in vivo, e realizar comparações da extração do material vegetal por calor (infusões) e extração a frio (extrato). Para isso, foram preparadas dois tipos de soluções, infusões e extratos foliares de P. punctatum, em duas concentrações 0,4 g mL-1 e 2,4 g mL-1. A infusão foi preparada pela adição das folhas secas em água destilada fervente (100ºC), permanecendo por 10 minutos enquanto o extrato foi preparado através da maceração das folhas secas em água destilada fria. Para o teste em A. cepa foram utilizados, para cada tratamento, seis grupos de quatro bulbos e seis caixas gerbox com 50 sementes em cada caixa. Duas lâminas para cada tratamento foram obtidas através da técnica de esmagamento das raízes e coradas com orceína acética 2%. Foram contadas 2000 células por grupo de bulbos e 3000 células por grupo de sementes, observando-se a ocorrência de interrupções em metáfases, alterações cromossômicas estruturais, bem como a inibição ou aumento da divisão celular. Os valores do índice mitótico foram calculados e analisados estatisticamente pelo Teste χ2 (p≤0,05). Os resultados demonstraram que as infusões e os extratos de folhas apresentaram redução nos valores de índices mitóticos nas concentrações utilizadas em relação ao controle em água destilada. Foram identificadas alterações cromossômicas na divisão celular, tais como pontes anafásicas, em todas as concentrações de infusões e extratos indicando assim que P. punctatum possui atividade antiproliferativa e genotóxica.

ABSTRACT: The species Polygonum punctatum Elliott (Polygonaceae) is widely used by the Brazilian population as a medicinal plant. The aims of this study are to evaluate the genotoxic and mutagenic potential of P. punctatum, using its root bulbs and rootlets in germinated seeds of Allium cepa by in vivo testing, and to compare the extraction of plant material by heat (infusions) and cold (extract). Thus, two types of solutions - infusions and leaf extracts - of P. punctatum were prepared at the two concentrations of 0.4 g ml -1 and 2.4 g mL- 1. The infusion was prepared by addition of dry leaves in boiling distilled water (100ºC), remaining for 10 minutes, while the extract was prepared by maceration of dried leaves in cold distilled water. For the A. cepa, we used for each treatment six groups of six bulbs and six seedling boxes with 50 seeds each. Two slides for each treatment were obtained by the technique of crushing the roots, and they were stained with 2 % acetic orcein. For the analysis, 2000 cells per group of bulbs and 3000 cells per group of seeds were counted, and we noted the occurrence of interruptions in the metaphase, chromosomal aberrations, as well as inhibited or increased cell division. The values of the mitotic index were calculated and statistically analyzed by the χ2 test (p ≤ 0.05). The results showed that the infusions and extracts of leaves showed reduced values of mitotic indices in the concentrations used compared to the control in distilled water. Chromosomal alterations were identified in the cell division, in all concentrations of infusions and extracts, thus indicating that P. punctatum has an antiproliferative and genotoxic activity.

Identification and Quantification of Flavonoids from Two Southern Italian Cultivars of Allium cepa L., Tropea (Red Onion) and Montoro (Copper Onion), and Their Capacity to Protect Human Erythrocytes from Oxidative Stress.

Onions (Allium cepa) are consumed worldwide and represent an important source of dietary phytochemicals with proven antioxidant properties, such as phenolic acids, flavonoids, thiosulfinates, and anthocyanins. Epidemiological and experimental data suggest that regular consumption of onions is associated with a reduced risk of degenerative disorders. Therefore, it is of interest to investigate the biological properties of different varieties of onions. Here, we characterized for the first time a variety of onion, called Ramata di Montoro (coppery onion from Montoro), grown in a niche area in southern Italy, and compared its phenolic profile and antioxidant properties to a commercial ecotype of red onion, Tropea, also present in southern Italy. An analytical method based on high-performance liquid chromatography coupled with UV detection and mass spectrometry was used to separate and characterize the phenolic fraction (anthocyanins and flavonols) extracted from both coppery and red types. The main compounds detected in the two ecotypes were quercetin and quercetin glucosides, isorhamnetin glucosides, kaempferol glucoside, and, among anthocyanins, cyanidin glucosides. Tropea ecotype onion showed a higher content of flavonols (632.82 mg/kg fresh weight) than Montoro type onion (252.91 mg/kg fresh weight). Accordingly, the antioxidant activity of the former was 2.8-fold higher compared to the latter. More pronounced were the differences existing between the four anthocyanins detected in the two ecotypes, with those in the Tropea ecotype onion present at concentrations 20-230-fold higher than in the Montoro type onion. Both extracts reduced LDL oxidation about 6-fold and protected human erythrocytes from oxidative damage induced by HClO by about 40%. In addition, as a consequence of HClO treatment, glutathione concentration in erythrocytes was reduced about 50% and pretreatment with onion extracts induced a recovery of glutathione level by about 15-22%. Qualitative differences highlighted in the chemical composition of the two phenolic extracts, especially the total content of anthocyanins, which was 30-fold higher in Montoro type onion compared to Tropea ecotype, can be associated with the protective effects measured against oxidative damage induced in human erythrocytes.

RNA-Seq reveals leaf cuticular wax-related genes in Welsh onion.

The waxy cuticle plays a very important role in plant resistance to various biotic and abiotic stresses and is an important characteristic of Welsh onions. Two different types of biangan Welsh onions (BG) were selected for this study: BG, a wild-type covered by wax, which forms a continuous lipid membrane on its epidermal cells, and GLBG, a glossy mutant of BG whose epidermal cells are not covered by wax. To elucidate the waxy cuticle-related gene expression changes, we used RNA-Seq to compare these two Welsh onion varieties with distinct differences in cuticular wax. The de novo assembly yielded 42,881 putative unigenes, 25.41% of which are longer than 1,000 bp. Among the high-quality unique sequences, 22,289 (52.0%) had at least one significant match to an existing gene model. A total of 798 genes, representing 1.86% of the total putative unigenes, were differentially expressed between these two Welsh onion varieties. The expression patterns of four important unigenes that are related to waxy cuticle biosynthesis were confirmed by RT-qPCR and COG class annotation, which demonstrated that these genes play an important role in defense mechanisms and lipid transport and metabolism. To our knowledge, this study is the first exploration of the Welsh onion waxy cuticle. These results may help to reveal the molecular mechanisms underlying the waxy cuticle and will be useful for waxy gene cloning, genetics and breeding as well as phylogenetic and evolutionary studies of the Welsh onion.

Quantitative metabolite profiling of edible onion species by NMR and HPLC-MS.

Allium genus is a treasure trove of valuable bioactive compounds with potentially therapeutically important properties. This work utilises HPLC-MS and a constrained total-line-shape (CTLS) approach applied to (1)H NMR spectra to quantify metabolites present in onion species to reveal important inter-species differences. Extensive differences were detected between the sugar concentrations in onion species. Yellow onion contained the highest and red onion the lowest amounts of amino acids. The main flavonol-glucosides were quercetin 3,4'-diglucoside and quercetin 4'-glucoside. In general, the levels of flavonols were, higher in yellow onions than in red onions, and garlic and leek contained a lower amount of flavonols than the other Allium species. Our results highlight how (1)H NMR together with HPLC-MS can be useful in the quantification and the identification of the most abundant metabolites, representing an efficient means to pinpoint important functional food ingredients from Allium species.

Triparental origin of triploid onion, Allium × cornutum (Clementi ex Visiani, 1842), as evidenced by molecular, phylogenetic and cytogenetic analyses.

BACKGROUND: Reconstruction of the parental origins of cultivated plants from wild relatives, especially after long periods of domestication, is not a trivial task. However, recent advances in molecular phylogenetics, among other approaches, have proved to be very informative in analyses of the origin and evolution of polyploid genomes. An established minor garden crop, triploid onion Allium × cornutum (Clementi ex Visiani, 1842) (2n = 3x = 24), is widespread in southeastern Asia and Europe. Our previous cytogenetic analyses confirmed its highly heterozygous karyotype and indicated its possible complex triparental genome origin. Allium cepa L. and Allium roylei Stearn were suggested as two putative parental species of A. × cornutum, whereas the third parental species remained hitherto unknown. RESULTS: Here we report the phylogenetic analyses of the internal transcribed spacers ITS1-5.8S-ITS2 of 35S rDNA and the non-transcribed spacer (NTS) region of 5S rDNA of A. × cornutum and its relatives of the section Cepa. Both ITS and NTS sequence data revealed intra-individual variation in triploid onion, and these data clustered into the three main clades, each with high sequence homology to one of three other species of section Cepa: A. cepa, A. roylei, and unexpectedly, the wild Asian species Allium pskemense B. Fedtsh. Allium pskemense is therefore inferred to be the third, so far unknown, putative parental species of triploid onion Allium × cornutum. The 35S and 5S rRNA genes were found to be localised on somatic chromosomes of A. × cornutum and its putative parental species by double fluorescent in situ hybridisation (FISH). The localisation of 35S and 5S rDNA in A. × cornutum chromosomes corresponded to their respective positions in the three putative parental species, A. cepa, A. pskemense, and A. roylei. GISH (genomic in situ hybridisation) using DNA of the three putative parental diploids corroborated the results of the phylogenetic study. CONCLUSIONS: The combined molecular, phylogenetic and cytogenetic data obtained in this study provided evidence for a unique triparental origin of triploid onion A. × cornutum with three putative parental species, A. cepa, A. pskemense, and A. roylei.

Flavonol content and biometrical traits as a tool for the characterization of "Cipolla di Giarratana": a traditional Sicilian onion landrace.

"Cipolla di Giarratana", a locally cultivated white onion landrace, is listed as an item in the 'List of Traditional Agro-food Products' of the Italian Department for Agriculture and itemised as 'slow food presidium' by the Slow Food Foundation. Ten local accessions were investigated for their biomorphological and biochemical characteristics in five experimental locations. High-performance liquid chromatography coupled with diode array detection and electron spray-mass spectrometry (HPLC/DAD/ESI-MS) was used to identify the phenolic profile and quantify phenolic content in bulbs: quercetin, quercetin 3,4' di-O-glucoside and quercetin 4'-O-glucoside were detected as major components. The 'Cipolla di Giarratana' landrace is characterised by a high bulb weight (436g) and high diameter (11cm). The total flavonols content ranged between 68 and 408mgkg(-1) bulb fresh weight in nine of the 10 collected accessions. The opportunity of considering flavonol patterns as chemotaxonomic descriptors in order to characterise onion germplasm is also discussed.

Bioaccessibility of flavonoids and total phenolic content in onions and its relationship with antioxidant activity.

Antioxidant activity, total phenolic content, and flavonoids in onion were determined using the DPPH method, the Folin-Ciocalteu method, and high-performance liquid chromatography analysis, respectively. Myricetin was the most bioaccessible among flavonoids in both red and yellow onions after digestion. The result suggest that the antioxidant activity of yellow and red onions was stronger in the outer layer than in the inner layer and strong correlation was found between antioxidant activity and total phenolic content (r(2) = 0.927).

Cluster analysis and artificial neural networks multivariate classification of onion varieties.

Eight cultivars of different colored onions (white, golden, and red) were evaluated for fresh bulbs cultivated and grown under the same environmental and agronomical conditions. Cluster analysis and principal component analysis, based on different flavonoids, total phenols, and pungency, data showed that the onions were not clustered according to variety (genetic similarity degree), whereas the color was the variable with the highest influence, ranging between 50 and 70%. Artificial neural networks were applied to study the possibility of discriminating among onion varieties. Characterization of the onion according to variety and procedence of the seeds was around 95-100%. Samples belonging to the Carrizal Alto procedence had an incorrect classification for 25% of the data.

Determination of the geographic origin of onions between three main production areas in Japan and other countries by mineral composition.

Onions (Allium cepa L.) are produced in many countries and are one of the most popular vegetables in the world, thus leading to an enormous amount of international trade. It is currently important that a scientific technique be developed for determining geographic origin as a means to detect fraudulent labeling. We have therefore developed a technique based on mineral analysis and linear discriminant analysis (LDA). The onion samples used in this study were from Hokkaido, Hyogo, and Saga, which are the primary onion-growing areas in Japan, and those from countries that export onions to Japan (China, the United States, New Zealand, Thailand, Australia, and Chile). Of 309 samples, 108 were from Hokkaido, 52 were from Saga, 77 were from Hyogo, and 72 were from abroad. Fourteen elements (Na, Mg, P, Mn, Co, Ni, Cu, Zn, Rb, Sr, Mo, Cd, Cs, and Ba) in the samples were determined by frame atomic adsorption spectrometry, inductively coupled plasma optical emission spectrometry, and inductively coupled plasma mass spectrometry. The models established by LDA were used to discriminate the geographic origin between Hokkaido and abroad, Hyogo and abroad, and Saga and abroad. Ten-fold cross-validations were conducted using these models. The discrimination accuracies obtained by cross-validation between Hokkaido and abroad were 100 and 86%, respectively. Those between Hyogo and abroad were 100 and 90%, respectively. Those between Saga and abroad were 98 and 90%, respectively. In addition, it was demonstrated that the fingerprint of an element pattern from a specific production area, which a crop receives, did not easily change by the variations of fertilization, crop year, variety, soil type, and production year if appropriate elements were chosen.

Application of inorganic element ratios to chemometrics for determination of the geographic origin of welsh onions.

The composition of concentration ratios of 19 inorganic elements to Mg (hereinafter referred to as 19-element/Mg composition) was applied to chemometric techniques to determine the geographic origin (Japan or China) of Welsh onions (Allium fistulosum L.). Using a composition of element ratios has the advantage of simplified sample preparation, and it was possible to determine the geographic origin of a Welsh onion within 2 days. The classical technique based on 20 element concentrations was also used along with the new simpler one based on 19 elements/Mg in order to validate the new technique. Twenty elements, Na, P, K, Ca, Mg, Mn, Fe, Cu, Zn, Sr, Ba, Co, Ni, Rb, Mo, Cd, Cs, La, Ce, and Tl, in 244 Welsh onion samples were analyzed by flame atomic absorption spectroscopy, inductively coupled plasma atomic emission spectrometry, and inductively coupled plasma mass spectrometry. Linear discriminant analysis (LDA) on 20-element concentrations and 19-element/Mg composition was applied to these analytical data, and soft independent modeling of class analogy (SIMCA) on 19-element/Mg composition was applied to these analytical data. The results showed that techniques based on 19-element/Mg composition were effective. LDA, based on 19-element/Mg composition for classification of samples from Japan and from Shandong, Shanghai, and Fujian in China, classified 101 samples used for modeling 97% correctly and predicted another 119 samples excluding 24 nonauthentic samples 93% correctly. In discriminations by 10 times of SIMCA based on 19-element/Mg composition modeled using 101 samples, 220 samples from known production areas including samples used for modeling and excluding 24 nonauthentic samples were predicted 92% correctly.

An onion variety has natural antithrombotic effect as assessed by thrombosis/thrombolysis models in rodents.

INTRODUCTION: Prevention of arterial thrombotic diseases has a high priority in developed countries. As inappropriate diet has been shown to be an important risk factor for thrombotic events, regular antithrombotic diet may offer a convenient and effective way of prevention. The aim of the present study was to test onion extracts for antithrombotic effect and to identify the effective varieties in Allium cepa. MATERIALS AND METHODS: A shear-induced platelet function test (haemostatometry) was used to screen for antithrombotic potential. Onion extracts showing significant antithrombotic activity in vitro were further assessed in vivo by using a laser-induced thrombosis test in mice. RESULTS AND CONCLUSIONS: An onion variety, Toyohira, showed significant antithrombotic activity both in vitro and in vivo. Toyohira showed thrombolytic activity in addition to the antiplatelet effect. Superkitamomiji, 2935A, and K83211 showed only thrombolytic activity. Quercetin, the richest flavonoid in onion, was measured, but no correlation was found between quercetin content and antithrombotic activity. It is concluded that onion A. cepa can be classified into varieties with or without antithrombotic and thrombolytic effects. This should be taken into account in future population studies on the antithrombotic effects of vegetables.

Resistencia Antimicrobiana: un problema en expansión / Resistance antimicrobic: in problem expansion

El folleto aborda acerca de la resistencia antimicrobiana de microorganismos multirresistentes, causantes de infecciones graves. La resistencia de E. coli no patógeno de un grupo de etáreo infantil de la ciudad de León